Magnetic moment of compass needle?

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shoestring
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What would be a typical value of the magnetic moment of a compass needle (in SI units)?

Thanks :-)
 
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Do you know the B field of the needle? If you do try to model the needle as a little current loop, Use the biot savart law to find what current your loop needs to produce that B field. Your loop will have a diameter equal to the length of the needle.
Then just multiply the current times area
M=I(area)
Maybe you could find the B field of the needle by dropping it through a coiled copper wire and relating the change in flux to the voltage .
 
Thanks both, but I'm a little confused about the units. The strength of a magnet is given in Tesla, but that isn't the same as magnetic moment, is it? Obviously I need to read up on magnetism.

The reason I'm wondering is that I'd like to compare the magentic dipole moment of a compass needle with the induced electric dipole moment it might get in a strong electric field, to see if an electric field could possible cause any deviation of the needle.